Growth Factors in Wound Healing Increase size of cells Increase number of cells Inhibit apoptosis Pleiotropic effects i.e initiate cell proliferation, migration,differentiation, contractility, enhance synthesis of specializedproteins eg. Collagen in fibroblasts Act in autocrine, paracrine, or endocrine manner
STEM CELLSHomeostatic relation between replication anddifferentiation of stem cellsCells differentiate progressively as they migrate into theupper layers of the epitheliumIn the skin stem cell niches are in the basal layerCharacteristics of Stem cells1. Self renewal capacity2. Asymmetric replication.
Regenerative MedicineRegenerative MedicineGoal:Goal: Regeneration and repopulation of damaged organusing embryonic or adult stem cells.Therapeutic CloningTherapeutic CloningPatients cell Enucleated oocyteNuclear transfer embryoNuclear transfer blastocystEmbryonic stem cellsBlood cells Neurons Muscle cells
Potential Therapeutic Strategies1. Transplanting stem cells into area of injury2. Use of stem cell systems to produce largeamounts of differentiated cells fortransplantation
Repair By Connective Tissue includes: Angiogenesis 1. Vasculogenesis2. Angiogenesis) Deposition of ECM Migration and Proliferation of Fibroblasts Maturation and Reorganisation of FibrousTissue.
Fetal Wound Healing Younger the fetus less noticeable is the scar Fetal fibroblasts even in adult transplantation heals with theabsence of inflammation Theory: that wound fibroblasts do not become myofibroblastsuntil late in gestation. IL6 is high in adult stimulated fibroblasts compared to fetalstimulated ones with coincides with increased inflammation inadults Thrombospondin 1 decreases with increase in gestation. Itdestabilizes matrix contracts in the EC space, facilitatesmitogenesis and chemotaxis. Promotes cell associatedprotease and self supports matrix turnover. Thus inflammationwould decrease and there would be less scarring
Aberrations of HealingAberrations of HealingKeloids: Females>Males Blacks>Whites/ Familial Outgrows the wound Rarely subsides leads to pathologic scarringin other areas ofthe body. In bones-Osteoarthritis common on the faceshoulders back andsternumHypertrophic Scar Females=Males Not race related/ familial Remains within the wound Subsides with time Flexor surfaces affected
1.compression bandages2. intralesional Triamcinolone3. Excision and skin grafting4. Laser5. Surgery f/b post op interstitialradiotherapyExcessive granulation tissue which protrudes abovethe level of the skin & hinders re epithelialisation iscalled “EXUBERANT GRANULATION or PROUDFLESH! Rx: Cautrise or surgically resect the tissueRx of Aberrations
Collagen & chondroitin sulphate : IntegraApligraftrade: skin substitute containing collagen andseeded cellsAlloderm: immunologically inert, nonliving, allogenic,acellular dermal matrix with intact basement membraneprepares wound bed for grafting
TegadermUsed for simple shallow wound dressingProtects from water loss mechanical injury and drying
TransCyte (ECM matrixgenerated by allogenichuman dermal fibroblastsserves as a matrix forneodermis generationORCEL: Composite culturedskin. Fibroblasts,keratinocytes seeded onopposite sides of bilayeredmatrix of bovine collagen
Dermagraftliving allogenic dermal fibroblasts grown on a degradablescaffold. Good resistance to tearing
E-Z DermBiosynthetic porcinederived xenograftCollagen has beencrosslinked with aldehydeCan be conveniently storedat room temperaturelong shelf life. perforated or non-perforatedPartial thickness, donorsites, sandwich autografts,and to cover full thicknesswounds prior to grafting.OASIScomprised of small intestinesubmucosa acellular collagenmatrix. Chance of rejection
beta-Glucan stimulates themacrophage activity and promotesrapid wound healing.Beta-Glucan Collagen mesh orGlucan II (Beta-Glucan) mesh.Rapid healing without dressingchangespainless treatment.
HONEYSOFTNatural dressingHoney-impregnated dressingChronic unhealing wounds.Impregnated into a compress ofEVA (ethylenevinylacetate) meshHoney cleans the wound withoutdisturbing itRemoving the dressing causes nodamageno known side effects
Hyperbaric Medicine Systemic delivery of oxygen to the tissuesunit which has been compressed toapproximately 2-2.4 ATA. Stimulates angiogenesis and fibroblastmigration, enhances neutrophil and antibiotickilling action, and suppresses alpha toxinproduction in gas gangrene.
Total Contact Casting A treatment used for successful offweighting ofplantar foot ulcerations. Provides decreased plantar surface pressuresover wounded areas of the foot, byredistributing weight bearing over the entirelower leg.
a novel hydrogel, to seal wounds and atthe same time deliver an antibacterialpunch"Theyre like rebarwhen youre buildingsomething withconcrete,They give the cementsomething to hangonto.""MAX8,"encapsulate livingcells in thehydrogel and theninject the gel intosecondary siteswithout harmingthe cells.